1) What's the difference between an RF Amp and any regular amplification circuit using something cheap like a 741? I would assume the RF amp's can operate at much higher frequencies.

That is about it. Making a stable amplifier at high frequency is no small trick.

2) Do RF Amps need to be tuned or do they just say they can handle signals up to 10Mhz and I can feed it any signal up to that value?

The output has to be filtered, or you'll be generating signals on frequencies other than the desired one. Remember amplifying devices are not linear (output = input time amplification), their outputs are a complex function of the input. Feedback systems help straighten their response out, but not completely.

3) Finally, does anyone know where I can get an RF amp for a pretty cheap price ? :)

RF Circuits sells Gain Modules that are Audio to several GHz and only need a few capacitors and inductors to make work, two or three bucks. What I would really recommend to you is to go to the library and check out the ARR. 199x or 200x Radio Amateur's Handbook. You will find many radio and amplifier circuits. If you copy exactly what is in there, you will end up with a circuit that works.
Also if your signal only needs to go 2 feet, you might consider just testing your modulator. It probably produces enough signal as it is to travel that distance.

Goo luck,
Pherd
Somers, CT

David VanHorn

... If it won t go a couple feet, it isn t working at all. -- Dave s Engineering Page: http://www.dvanhorn.org Got a need to read Bar codes?

Message 2 of 3
, Oct 1, 2001

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>
> RF Circuits sells Gain Modules that are Audio to several GHz and
> only need a few capacitors and inductors to make work, two or three
> bucks. What I would really recommend to you is to go to the library and
> check out the ARR. 199x or 200x Radio Amateur's Handbook. You will find
> many radio and amplifier circuits. If you copy exactly what is in there,
> you will end up with a circuit that works.
> Also if your signal only needs to go 2 feet, you might consider
> just testing your modulator. It probably produces enough signal as it is
> to travel that distance.

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